Retractable mechanism of pinch yoke type



1959 w. B. SPATZ 2,868,170

RETRACTABLE MECHANISM OF PINCH YOKE TYPE Filed Oct. 14, 1953 2Sheets-Sheet 1 29 u PVILTEQ B. SPA 3 RETRACTABLE MECHANISM OF PINCH YOKETYPE Walter B. Spatz, Los Angeles, Calif, assignor, by mesneassignments, to Paper Mate Manufacturing Company, Culver City, Calif acorporation of Delaware Application October 14, 1953, Serial No. 385,9732 Claims. (Cl. 120-42113) This invention relates to writing instrumentsespecially of the ball point pen type and more particularly relates toan improved mechanism for extending and retracting the writing elementof such instruments.

It is now quite feasible to construct a ball point writing instrumentwith a writing element movable from an extended writing position to aretracted carrying position. Such an instrument is not generally subjectto leakage,

avoids the use of an inconvenient separate cap, and may be convenientlycarried with its writing element retracted and instantly readied foruse.

The prior art discloses a rather large number of mechanisms directedtoward providing suitable extending and retracting mechanisms for ballpoint writing instruments, but in general such mechanisms are subject toa number of persistent disadvantages which are inherent orcharacteristic of all such types of mechanisms. Thus, in general it isnecessary to provide an operating mechanism which involves a rathercomplex device to he compacted into a relatively small confined space.Such a device must necessarily include rather tiny and intricate parts.In most prior types of retracting mechanisms these parts have beennumerous, delicately related and attached to each other, expensive tomanufacture, and very difiicult to assemble. As a natural and expectedconsequence the parts may wear out, or become distorted or misaligned,to cause the mechanism to jam, become difficult to operate, or evenbreak down completely. Accordingly, a suitable retracting mechanisminvolving a minimum number of direct acting elements economical tomanufacture, capable of being easily assembled into a device which iseasy to operate, positive and dependable in operation and sufficientlyrugged to withstand the hard use of a large number of operations withoutfailure, is much to be desired.

With the foregoing in mind it is a principal object of the invention toprovide an improved retractable ball point pen of simple and durableconstruction.

It is another object of the invention to provide an improved retractingmechanism for writing instruments which is easy to operate, convenientlyused, positive and dependable in operation, and sufficiently rugged towithstand the hard use of a large number of operations without failure.

It is another object of the invention to provide an operating mechanismfor Writing instruments having a positive and direct acting means forurging a writing element into an extendedwriting position.

It is a further object of the invention to provide an operatingmechanism for writing instruments having a simple direct acting andpositive locking means for holding a writing element in an extendedposition.

It is a still further object of the invention to provide an operatingmechanism having a minimum number of sirn-' ple relatively ruggedworking parts permitting of easy and rapid assembly and capable ofwithstanding hard use.

It is a further object of the invention to provide a re tractingmechanism for writing instruments operable by ICC means of a carryingclip at the upper end of the writing instrument.

These and other objects and advantages of the invention will becomeapparent from the following detailed description of the preferredembodiment thereof and from an inspection of the accompanying drawingsin which:

Fig. 1 is an elevational view partly in section of my retractablewriting instrument.

Fig. 2 is an enlarged longitudinal sectional view of the upper caseshowing the operating clip released and the writing element in itsnormal retracted position.

Fig. 3 is a transverse section through IIIIIII of Fig.

Fig.4 is a transverse section through IV-IV of Fig. 2.

Fig. 5 is a transverse section through VV of Fig. 2.

Fig. 6 is a transverse section through VI-VI of Fig. 2.

Fig. 7 is a sectional View of the upper case, similar to .Fig. 2,showing the operating clip depressed and the writing element in fullextended position.

Fig. 8 is a sectional view of the upper case, similar to Fig. 2, showingthe operating clip released and the Writing element extended in normalwriting position.

Fig. 9 is a sectional view of the upper case similar to Fig. 2, showingthe operating clip depressed and the writing element retracted.

In general, the invention contemplates the provision of a mechanism forextending and retracting the writing element in ballpoint pen typewriting instruments, to be used in conjunction with awriting instrumentwherein the writing element is movable axially into retracted andprojected positions, and wherein spring means normally biasing thewriting element into retracted position are provided. The mechanism of'the invention includes a sleeve carried by the upper end of the writingelement provided with a lug extending laterally and annularly around itswall, a push rod which is movable longitudinally and laterally withrespect to the sleeve, a pinch yoke resiliently biased into a sleevegrasping position, suitable upwardly pinch yoke grasps it. The writingelement is retracted.

when the push rod is again urged longitudinally downward and cams on thecamming surface of the upper case into engagement with the sleevegrasping portion of the pinch yoke releases its grasp and allows thewriting unit to retract under its normal bias.

Referring now to the drawings the reference numeral 10 generallydesignates a writing instrument. which is one embodiment of theinvention. 10 includes a writing element 11 having an upper inkcarryingcartridge 12, and a lower ink dispensing tube- .13. The tube 13 isprovided at its extreme lower end 14, with a socket to retain a ballpoint 115. The cartridge 12 may be encased in a sleeve 16, having a lipportion 17. to limit its downward motion on the cartridge 12, and a lugportion 18, for a purpose to be more particularly explained.

The writing element 11 is preferably slidably supported in housingconsisting of a lower case portion 19 with a downwardly directed port20, through which the extreme lower end 14 of the writing element 11 maybe projected, and an upper case portion 21 which may include a slottedouter shell 22, and an inner body member 23. The lower case 19 and theupper case 21 are preferably adapted to be screw threaded together so 1that they may be disengaged to permit replacement of V the writingelement 11.

The writing instrument a The writing element '11 is biased upwardly intoretracted position by a retracting spring 24 positioned between the case19 and the elementll.

The body member 23 is preferably a substantially cylindrical moldedmember which may be press fittedinto the outer shell 22 to form theupper case portion 21. The member 23 may be, provided with an axial bore25 having upwardly and downwardly directed openings 26 and 27respectively. At the upper end of the member 23 the opening 26 may beconsiderably widened.

Within the widened upper portion of the axial bore 25, a downwardlydirected shoulder 28 may be formed to contact the upper end of thewriting element 11 and arrest its upwardly biased movement. For apurpose to be moreparticularly illustrated an offset channel or groove29 may be provided adjacent and communicat ing with the axial bore 25and two radial slots or wells 30, 31 maybe provided in the outer wall ofthe member 23.

Operating means may comprise a normally upwardly biased member movableaxially of the case and extend ing from the upper case portion 21. Suchmeans may comprise a plunger 32 provided with an upstanding pin 33, thepin extending upwardly through opening 34 formed in the upper end of theupper shell 22. Although a clip may be attached to the case 21 in anysuitable manner, the drawings illustrate an embodiment wherein the clip35 is attached to the pin 33, as by threads or a press fit, and ismovable therewith. The plunger 32 is provided with a conical lower endloosely fitting into axial bore 25 of body member 23 and is connected toa push rod or operating arm 36 extending downwardly adjacent the writingunit 11.

The operating arm of push rod 36 may be provided with a ported portion37 encircling the pin 33 and downwardly extending rectilinear portions38 and 39 connected by a curved or inclined camming portion 40. Thelower end of the push rod 36 may be provided with a spatulate portion 41having a concave face facing the writing element. The push rod extendsthrough the offset channel slot or groove 29 formed in body member 23adjacent and communicating with the axial bore 25. The opposite end 42of the push rod 36 is bent downwardly as shown and is preferably widerthan slot 43 in the upper case, thereby closing said slot. Upward biasis imparted to the operating means by a return spring 44 surrounding thelower end of the plunger 32 and bearing against the upper end face ofthe body member 23 and the ported portion 37 of the push rod 36.

Means are provided for holding the writing implement 11 in projectedwriting position. Such means comprise a pinch yoke in the form of asubstantially planar annular member 45 provided with a blade portion 46,the end of the blade being firmly attached to the body member 23 as bymeans of the anchor 47. The entire pinch yoke is made from resilientmaterial, the annular portion being bent to occupy a plane at less than90 to the axis of the writing cartridge and the blade or tongue. Theannular portion includes non-parallel spaced faces providing an apertureslightly larger than the diameter of the cartridge or writing unit or ofthe sleeve 16 carried thereby, the spaced faces receiving therebetweenthe writing unit and normally grasping the unit. In the event the inkreservoir of the writing unit is of metal, the sleeve 16 need not beemployed, since the lug 18 may be formed integral with the cartridge;since the pinch yoke in its operative position actually grasps cartridge12 and some cartridges are made of resinous or plastic materials whichare readily indented and deformed, the metallic sleeve 16 is preferablyused in order to prevent deformation or impairment of the cartridge.

Means are provided to guide and control lateral motion to push rod 36 soas to permit the spatulate end 41 to contact lug 18 upon depression ofthe pin 33 (when the writing unit is retracted) and thereby move thewriting unit into projecting position, and upon a second depression ofthe pin 33 to cause the end of the push rod 36 to contact the pinch yokeand release its grip upon the writing unit, thereby allowing biasingspring 24 to retract the writing unit. Such means may comprise a guidesurface, camming wall, or inclined camming shoulder 48 formed in theouter wall of groove 29 of body portion 23, such camming shouldercooperating with camming portion 40 of the push rod 36. It will be notedthat rectilinear portion 38 of the push rod is yieldably urged laterallyagainst the wall of groove 29 by reason of the resilient pressure of end42 against the inner wall surfaces of case 21 adjacent slot 43, but aslong as camming portion 40 is in contact with the outer wall of groove29 above shoulder 48 the spatulate end 41 will engage lug 18 of thewriting unit.

Operation of the retractable writing instrument is as follows: when thewriting instrument is in a carrying or retracted condition, its partsare positioned as shown in Fig. 2. The writing element 11 is fullyretracted under the influence of the retracting spring 24. Pin 33,plunger 32 and clip 35 are in up position and the push rod 36 is againstthe wall of the body member 23, with its spatula-shaped end 41 near toengagement with the lug 18.

When pin 33 or plunger 32 is depressed, push rod 36 moves longitudinallyand compresses the return spring 44. Simultaneously, as it moveslongitudinally, the push rod 36 engages lug 18 and moves the writingelement into fully extended position as shown in Fig. 7.

As soon as plunger 32 or clip 35 is released, the spring 44 is able toextend and return the plunger 32 and the push rod 36 to the positionsshown in Fig. 8. However, the writing element is held in projectedwriting position through the pinching action of the annular member 45 onthe sleeve 16. Moreover, due to the inclination of the annular member 45with respect to the sleeve 16, its pinching action becomes morepronounced with any retracting tendency of the writing element. Thepositions of the parts when the writing element is fully extended areshown in Fig. 8.

Upon the next depression of the clip 35, the push rod 36 again is causedto move longitudinally, but this time the camming portion 40 of the pushrod 36 slides over the camming shoulder 48 of the body member 23 andguides the spatula-shaped end 41 laterally outwardly beyond lug 18 andinto aligned engagement with lip 49 of annular member 45 as shown inFig. 9. By this action, the annular member 45 is sprung open and causedto release its grip on the sleeve 16, and under the influence of theretracting spring 24, the writing element 11 retracts.

When the operating clip is released the plunger 32 and the push rod 36are returned to their normal fully retracted positions shown in Fig. 2.

It will be noted that the usual type of clip includes a number of smallparts and a leaf spring which yieldingly presses the clip toward theouter surface of the shell or case of the writing implement. In theembodiment illustrated, the clip 35 may be a simple solid one-pieceelement, some lateral yield being imparted to the lower or free end ofthe clip by the resiliency of the operating arm 36 and end 42 as theybear against the groove and inner surface of the shell.

Having fully described my invention, it is to be under stood that I donot wish to be limitedto the details herein set forth, but my inventionis of the full scope of the appended claims.

I claim:

1. In a writing instrument including an upper case portion provided withan upper body portion therein, said upper body portion having an axialbore adaptable to slidably receive the upper end portion of a writingunit, and a longitudinal groove adjacent said bore: a writing unitcarrying a lug, said writing unit extending into the 5 axial bore; anaxially movable, upwardly biased actuating member extending from theupper end of the case portion; an actuating arm attached to saidactuating member and extending downwardly through said groove, saidactuating arm being resiliently biased laterally away from the writingunit and lug thereon; means on the upper body portion for positioningsaid actuating arm proximate to said writing unit when said arm is inretracted position for alignment and engagement of said arm with 7 saidlug at a predetermined portion of its travel in said groove to move thewriting unit longitudinally with it for projection of the unit; and alongitudinally extending resilient blade provided with a virtuallytransversely extending pinch yoke at one end, the other end of saidblade being fixed in the upper case portion, said pinch yoke graspingsaid writing unit to resist upward movement of the writing unittherethrough, said writing unit being upwardly biased into retractedposition and said pinch yoke extending laterally of the axis of thewriting unit a greater distance than said lug and disposed below saidlug, said positioning means at another portion of travel of said armpermitting said arm to move laterally outwardly for passing over andbeyond said lug for engagement of the actuating arm with the pinch yoketo release the grasp of the pinch yoke upon the writing unit to permitupward travel of the unit into retracted position.

2. In a writing instrument including an upper case portion provided withan upper body portion therein, said upper body portion having an axialbore adaptable to slidably receive the upper end portion of a writingunit, and a longitudinal groove adjacent said bore: an upward-; lybiased writing unit extending into the axial bore and provided with alug; an upwardly biased actuating member extending from the upper end ofthe case portion and axially movable with respect thereto; an actuatingarm attached to the actuating member and extending downwardly throughsaid groove alongside said writing unit, said actuating arm beingresiliently biased laterally away from the writing unit and lug thereon;means on 6 the upper body portion for positioning said "actuating armproximate to the writing unit when the arm is in retracted position foralignment and engagement of said arm with said lug at a predeterminedportion of its travel in said groove to move the writing unitlongitudinally with it for projection of the unit; and a resilient bladeextending longitudinally along said writing unit and provided with atransversely extending pinch yoke at one end, the other end of the bladebeing fixed in the upper case portion, said pinch yoke having aninclined position relative to the axis of the writing unit to grasp thewriting unit to resist upward movement of the writing unit therethrough,said positioning means on the upper body portion at another portion oftravel of said "arm cooperating with said arm to guide said arm int-oengagement with said pinch yoke for moving said yoke out of saidinclined position to release said writing unit for movement thereof intoretracted position.

References Cited in the file of this patent UNITED STATES PATENTS1,726,011 Ziegler Aug. 27, 1929 2,500,439 Tursky Mar. 14, 1950 2,505,267Weber Apr. 25, 1950 2,514,610 Schweitzer July 11, 1950 2,526,268 PerraudOct. 17, 1950 2,584,569 Frentzel Feb. 5, 1952 2,692,580 Kahn et al. Oct.26, 1954 2,715,888 Liguori Aug. 23, 1955 FOREIGN PATENTS 53,926 GermanyOct. 10, 1890 2,838 Great Britain of 1896 934,235 France Jan. 10, 1948608,084 Great Britain Sept, 9, 1948 964,025 France Ian. 18, 1950 809,514Germany July 30, 1951 814,568 Germany Mar. 11, 1952

